This invention relates generally to digital telephones, and more particularly to an electronic switch for supplying power to the circuitry of a digital telephone.
The well known and traditional analog type telephones consume virtually no power when the telephone is on hook. The telephone circuitry is alerted by a high voltage signal which causes the bell at the telephone to ring. When the receiver of the telephone is picked up causing the telephone to go off-hook in response to a ring, the telephone begins to consume power.
New standards are being proposed which will result in digital services replacing existing analog telephones, such digital services including voice and high speed data transmission capabilities. Unlike analog telephones, the circuitry of a digital telephone must typically remain active in order that an incoming signal be detected. Typically, power consumption in the idle state is on the order of 200 milliwatts including line and conversion losses. This has been true notwithstanding that during idle conditions, nonessential circuits are deactivated to reduce power consumption. Forthcoming recommendations suggest that idle power consumption be less than 100 milliwatts with a goal of 25 milliwatts.